Stuff at sea -- it floats around (7)
I believe the answer is:
satiate
'stuff' is the definition.
('satiate' can be a synonym of 'stuff')
'at sea it floats around' is the wordplay.
'floats around' is an anagram indicator.
'at'+'sea'+'it'='atseait'
'atseait' anagrammed gives 'SATIATE'.
(Other definitions for satiate that I've seen before include "Completely satisfy" , "Have more than enough" , "gladden a gourmand" , "Overstuff" , "Gratify fully" .)